The stronghold of the U?Cheinnsealaigh (Hy Kinsella) Clan which subsequently
adopted the Caomhánach name was in South East Leinster, encompassing the modern counties of Wexford and Carlow,
with parts of Counties Wicklow, Kilkenny and Laois.

The U?Cheinnsealaigh initially rose to power in Leinster under a chieftain
called Diarmaid Mac Maol na mB?who became king of Leinster and also of Viking Dublin, in 1032. He subsequently
ruled over the Isle of Man and exercised influence in Western Scotland and Wales, as well as assisting the
future King Harold of England. Subsequent to Harold’s defeat by the Norman William the Conqueror his sons fled
for help to Mac Maol namB? He was the most powerful King in Ireland of his time up until his death in battle in 1072.

Following Mac Maol na mBó’s death,
the U?Cheinnsealaigh were embroiled in various conflicts involving
the quest for overall power in Ireland initially by the by the
O’Briens and subsequently by the O’Connors.

Mac Maol na mBó’s greatgrandson,
Diarmaid McMurrough (1110 ?1171; see separate article under
'Origin' on Home Page) was no sooner elected chieftain of the clan at
16 years of age in 1126, than his territory was invaded and ravaged
by the power-hungry O’Connor clan of Connacht together with the
malevolent Tiarnan O’Ruairc, King of Breffni, who was thereafter
Diarmaid’s bitter enemy. Some years later these enemies decided to
destroy him and Diarmaid was forced to seek assistance from overseas
in 1166.

Diarmaid hired Norman-Welsh mercenaries, under a leader known as Strongbow, Earl of Strigoil (and Pembroke). Strongbow was offered the hand of Diarmaid’s daughter Aoife and Diarmaid further promised the mercenaries territory in South Wexford, which belonged partly to the Norse and partly to an Irish clan which had betrayed him earlier.

The main body of these mercenaries arrived in 1169, and having recovered his ancestral territory with their assistance, Diarmaid was about to expand his conquests, probably with a view to replacing O’Connor as High King, when he was struck down by a mortal illness in 1171.

Following the death of Diarmaid
McMurrough (MacMurchadha) the Norman barons began to strike out and seize Irish
territories for themselves, whereupon the Norman King Henry II came over with a major army principally to
ensure that his barons did not carve out an independent Norman kingdom.

Diarmaid’s son Domhnall succeeded him
as elected King of Leinster, but he was assassinated at the behest of the Normans in 1175 as he was organizing
resistance against them.

Domhnall’s successors were recognized as the leading family in Leinster by the other
Irish clans and continued to claim the Kingship of Leinster right up to the beginning of the 17 th century. However,
their ancestral territories were under continual threat, initially from Norman, and later English, settler aggression.
Preserving their hold on their birthright meant a struggle for survival over the succeeding centuries with varying degrees
of success against a ruthless enemy who used every means possible, including regular resort to murder, in order to seize
Caomhánach ancestral territory.

Art Óg Caomhánach (1357 - 1417)
succeeded his father Art Mór (who died mysteriously in English custody)
in 1377 and began a series of campaigns which enabled him to recapture Caomhánach ancestral territory which had been lost.

King Richard II of England, attempting to restore his control over the Caomhánachs and other Irish
Clans, landed with one of the largest armies ever seen in Ireland at Waterford City in 1394.

After an initial display of defiance, including the burning of New Ross, Art Óg decided that a token submission was wisest path. King Richard
returned to England a few months later. The Caomhánachs, however, immediately went on the offensive again, killing Roger Mortimer, the heir
to the English throne at the Battle of Kellistown, Co.Carlow in 1398. A furious Richard II assembled another huge army and returned to Ireland
in 1399, with the avowed intention of finally eliminating Art.

Art Óg, recognizing that his advantage lay in carrying on a campaign of guerilla tactics, devastated Richard's army as he endeavoured to
pursue the rebel Irish army into its natural fastness. This famous victory has become the stuff of Irish legend.

Art Óg now held complete sway over the U?Cheinnsealaigh territory, which he further enlarged, through which none travelled without his permission.

Finally, on January 1st, 1417 the great Art Óg was assassinated, allegedly with a cup of poisoned wine

Upon Art Óg’s death, his son Domhnall received the Carlow lands west of the Blackstairs mountain range,
while his other son Gerald received the lands in Wexford, east of the mountains. The descendants of Gerald's son, Domhnall Reagh, became
the senior ruling line of the Caomhánach Clan. Domhnall Reagh's son, Art Bui, and grandson Murtagh, succeeded in maintaining the Clan's
independence despite continuing settler encroachment.

The Kavanagh Charter Horn

This ceremonial drinking horn
is one of only a handful of surviving relics that can be
linked personally to an Irish king. The Horn dates from
the early 12th century. Originally constructed from
elephant ivory the brass mountings were added much later
in the 15th century. Passed down through the MacMorrough
Kavanagh line it now rests in the National Museum of
Ireland.

The Chieftainship of the Clan continued in the senior line through the descendants of Domhnall Reagh.
The protection of Clan lands was only achieved at the expense of continuous warfare, with Cahir Carach Caomhánach being killed in 1538
and his son Donnchadh executed in 1583. Donnchadh's son, the famous Domhnall Spáinneach, was regularly in rebellion and was an ally of
the Great Hugh O’Neill during the Nine Years War (1594 -1603). Though Domhnall was finally forced to come to terms with the English
administration after the Battle of Kinsale in 1601, he retained a substantial part of his lands and was feared by the settler foes up
until his death of old age in 1632.

The defeat at Kinsale, however, signalled the final destruction of the old Gaelic clan system.

Domhnall Spáinneach's son, Sir Morgan, continued the fight for his ancestral territory as a leader
in the 1641 Rebellion during the course of which he was slain in battle in1643. Sir Morgan's sons, Domhnall Óg and Charles, continued
the fight with their father's regiment for the Catholic Confederacy until the rebellion was finally crushed by the armies of Oliver
Cromwell in the early 1650s.

After a period of imprisonment, Domhnall Óg chose to go into exile to join the Spanish army, while his brother Charles remained on in Ireland in
the hope of fighting another day. This opportunity came when Col. Charles raised a regiment for the Jacobite cause in 1689 but, following the defeat
of the Jacobite cause, he was killed in an accidental explosion aboard a prison ship off Kinsale in 1691.

This effectively marked the end of the ancient Caomhánach leadership in Leinster. Subsequent Caomhánach military achievements were chiefly in exile
in the service of the armies of Austria, France, Poland, Germany, and the Americas.

Those of the Clan who managed to remain in Ireland ended up as tenants of alien landlords for the most part.